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Warming to his subject

Philander traces transformation of El Niño

By Peter Page

Princeton NJ -- In 1997, it seemed that people were blaming just about anything on El Niño. The cyclical warming pattern in the waters off the coast of Peru was causing unusually severe weather, prompting media, governments, corporations and people around the world to latch onto it as the cause for a host of afflictions.

George Philander

In his new book, "Our Affair With El Niño: How We Transformed an Enchanting Peruvian Current Into a Global Climate Hazard," Princeton geoscientist George Philander examines the factors that contributed to the prominence and notoriety that El Niño suddenly gained in 1997. The book describes how developments in science, economics and politics shaped our perception of this natural phenomenon. It also explores the thorny issues that arise when, on the basis of scientific information with inevitable uncertainties, people try to cope with global environmental problems, including El Niño and global warming.

"A century ago, El Niño was considered a local event and a blessing because it brought rain to the desert of Peru," Philander said. In 1957, global data collection revealed that El Niño is not a regional phenomenon near South America, but an oceanic warming that affects global weather. For a while the phenomenon was a curiosity known to few, but in 1997, the term suddenly leapt into public consciousness and was blamed for disastrous weather all over the world.

"El Niño never changed but our perception of it changed," said Philander. "One important reason was that, as we grow in wealth and in population, so does our vulnerability to natural hazards. The El Niño of 1997, the most intense of the century, highlighted that paradox." Severe storms, earthquakes and other natural disasters cause far more damage today than in the past, not because they are more numerous or more intense, but because we have more possessions that can be destroyed, he said.

Philander draws parallels between the efforts to cope with El Niño, which naturally occurs roughly every five years, and the desire to deal with climate change and global warming driven by the burning of fossil fuels. In both cases, Philander notes, political leaders and policy-makers long for reliable scenarios about the future. And in both cases, science can make only limited predictions.

"Scientific research is almost never so conclusive that difficult political decisions become easy," Philander said. "For a long time we've had enough scientific information to know that a continual increase in atmospheric carbon dioxide (the major greenhouse gas from burning fossil fuels) will create serious problems. Addressing the problem requires difficult political decisions people don't like to make. Instead, they insist on more research."

Philander illustrates this point as he tells the story of scientists who studied El Niño and how their work influenced political events as well as how political events influenced their scientific work. El Niño first figured into Western scientific thinking because of the epic famines of 19th-century India that followed the occasional failure of the monsoon rains. British colonial administrators reasoned they could address famine by anticipating the failure of the monsoons. Gilbert Walker, a brilliant English mathematician, studied the problem for years and discovered an oscillation in winds that decades later proved to be a key element of El Niño.

Walker showed that this oscillation of the winds was related to failure of the monsoons, but was never able to use that information to predict the monsoons. In the end, the finding did nothing to relieve famine in India, Philander said.

"An easy way to avoid decisions is to say we need more information," Philander said. "The British had to do something about famine so they studied the weather. When India became independent, it treated famine as an economic problem by recognizing that its cause is often not a lack of food, but a failure to distribute food. During a drought, they employ farmers on public works so they can buy food. The government doesn't need to know for certain if it will rain next year to take effective action."

Nearly 100 years later, the uncertainties associated with El Niño have not gone away. Philander contrasts two forecasts that scientists made for the winter of 1997-98 predictions for a very wet winter in California and a very dry season in Zimbabwe. California cleared ditches and improved drainage. When the heavy rains came, the harm was minimized.

Zimbabwe was not so lucky. Based on the forecasts, bankers denied loans to farmers for fear that drought would stunt crops and prevent farmers from repaying their debts. The rains turned out to be plentiful; however, as a result of the mistaken precautions, the harvest was 20 percent below average.

"The prediction of a drought in effect caused a drought," Philander writes.

The differing outcomes in California and Zimbabwe illustrate the pitfalls of giving too much weight to scientific predictions, which always have an element of uncertainty, when shaping government policy. They also offer a warning to scientists, who, Philander said, face increasing pressure to justify their research by demonstrating practical applications, such as the ability to predict long-term changes in climatic conditions.

"An easy way to avoid decisions is to say we need more information . . ."

These difficulties, in turn, point up a broader problem that forms a major theme of Philander's book: the need to improve communication between scientists and non-scientists. The trouble, Philander writes, is not so much a lack of understanding of scientific terms and concepts among the general public as it is a difference in the way scientists and non-scientists approach problems. The scientific challenge of predicting El Niño, for example, is very different from the social and political challenge of preparing for El Niño, Philander writes.

"The methods and skills required to solve the problems encountered in the cold, uncompromising world of science have very limited applicability in the world of human affairs where compassion is a virtue, compromise a requisite," Philander writes.

Nonetheless, Philander devotes a section of the book to exploring common ground between painters, poets, musicians and scientists. There are remarkable parallels, for example, between the process a painter uses to depict a three-dimensional landscape and the approach scientists take in capturing the complexities of weather in a computer model. "We invoke certain rules," Philander said. "In the same way there are rules that allow you to convey things in perspective, we have rules for constructing computer models."

Philander concludes his book by arguing that our considerable experience in coping with the vagaries of the weather, El Niño and other natural hazards offers valuable lessons about how to deal with the prospect of global warming. We can take action to slow the buildup of carbon dioxide in the atmosphere and can do much to mitigate the disasters that global warming is likely to bring, even in the absence of precise predictions, he contends.

Philander acknowledges that issues related to global warming are politically charged, and hopes that the study of El Niño, which already has played out again and again, will provide a model for how to deal with critical problems of weather and climate in the face of uncertainty.

"El Niño is a natural phenomenon that can be blamed on nobody," he said. "So it gives us an objective way to consider the problem."